Larger than life

Just how big can containerships get?

There are known conceptual assessments of bigger containerships of around 22,000 teu-24,000teu, which will potentially be up to 50m longer.

Current large containerships have breadth consistent with carriage of 22 or 23 stacks abreast on deck. The capacity then becomes a function of vessel length.

However, it is considered that the industry is nearing the upper limit of creating capacity increases through greater length alone. More boxes will be squeezed into the current breadth limit, but it is unlikely that vessel capacity will exceed 22,000 teu without increasing the breadth.

It is unlikely that very small values of L/B will predominate, so the lesser values of length in are unlikely to represent the upper limits which we will be seen on ship length. Equally, ship length comes at a price, so it unlikely that high L/B values will dominate.

So it seems that 450m length overall is a realistic upper limit for vessel length for the foreseeable future – so the design of berths for the very largest anticipated container ships should be predicated on a vessel length of 450m.

The development of 22,000 teu vessels will be by means of increasing length, with 430m-433m being the likely dimension. There are two options for 24,000 teu vessels – either further lengthening with a slightly deeper draft, or a shift to broader vessels on a length of up to 430m. This would entail an additional row of containers.

It is realistic to anticipate that 22,000 teu vessels with a length of around 430m+ and 23 rows wide will be deployed on the Asia-Europe trades. The shift to 24,000TEU+ vessels will be more complex and would involve significant infrastructure and container crane investments.